1. Field
The present disclosure relates generally to electrical power systems and, in particular, to electrical power systems on aircraft. Still more particularly, the present disclosure relates to a stable electrical power system with a regulated transformer rectifier unit for providing power for active and passive direct current loads on an aircraft or other platform.
2. Background
Various systems and devices on an aircraft may use electrical power. For example, without limitation, electrical power may be used by a flight control system, in-flight entertainment systems, computers, actuators, lights, fans, pumps, or other systems and devices on an aircraft. Some systems and devices on an aircraft may use direct current, DC, power. Other systems and devices on an aircraft may use alternating current, AC, power. Electrical loads on an aircraft may include active loads and passive loads.
Electrical power for systems and devices on an aircraft may be provided by an electrical power system. An electrical power system on an aircraft may include various sources of electrical power and various structures for delivering electrical power from the electrical power sources to various systems and devices on the aircraft. An electrical power system on an aircraft may include a number of sources of AC power, a number of sources of DC power, or both. For example, without limitation, electrical power may be delivered from various power sources to various systems and devices that use electrical power on an aircraft via a number of buses. AC power may be provided from a number of AC power sources to systems and devices on the aircraft that use AC power via a number of AC buses on the aircraft. DC power may be provided from a number of DC power sources to systems and devices on the aircraft that use DC power via a number of DC buses on the aircraft.
AC power on an aircraft may be provided by a number of generators, by a number of other appropriate AC power sources, or by various combinations of AC power sources. Generators for providing AC power on an aircraft may be driven by the aircraft engines, in another appropriate manner, or in a combination of appropriate manners.
An AC-to-DC converter may be one example of a source of DC power on an aircraft. AC power may be converted to DC power by a number of AC-to-DC converters on an aircraft. For example, without limitation, an AC-to-DC converter may be configured to receive AC power provided on an AC bus on the aircraft by an AC power source and to provide DC power on a DC bus on the aircraft. An AC-to-DC converter on an aircraft may be configured to provide DC power at a desired voltage for use by various systems and devices on the aircraft from the AC power provided on the AC bus lines by the AC power source.
An AC-to-DC converter on an aircraft may be implemented as a transformer rectifier unit. A transformer rectifier unit comprises a transformer and a rectifier. For example, without limitation, a transformer in a transformer rectifier unit on an aircraft may be configured to transform a multiple-phase AC input signal provided by an AC power source to a multiple-phase AC output signal. The transformer may be configured to transform the voltage, phase, other characteristics, or various combinations of characteristics of the multiple-phase AC input signal received by the transformer to provide the multiple-phase AC output signal. The rectifier in the transformer rectifier unit may be configured to convert that multiple-phase AC output signal provided by the transformer in the transformer rectifier unit to a DC power signal.
It may be desirable that the quality of the DC power provided by an AC-to-DC converter on an aircraft is adequate under various operating conditions. It also may be desirable that an electrical power system including an AC-to-DC converter on an aircraft is stable. It also may be desirable that the weight of an AC-to-DC converter on an aircraft is reduced.
Therefore, it would be desirable to have a method and apparatus that take into account at least some of the issues discussed above, as well as other possible issues.